Motorcycles used for off-road racing or riding typically utilize oil-containing forks designed to absorb large impacts such as may be encountered during off-road racing or riding. However, providing for high impact events often leaves undesirable performance characteristics, such as a bumpy, harsh ride, when relatively small impact events are encountered. Typically, each front fork is a shock absorber provided by an enclosed cylinder having valving shims (or disks), a spring, oil and air space. A harder ride is achieved by minimizing the air space, while a softer ride is achieved by maximizing the air space.
The disclosure relates to a ride control system for a motorcycle having an oil-containing fork having an air space. In a preferred embodiment, the control system includes a control unit having a reservoir and a valve in flow communication with the air space of the fork and the reservoir. The valve is configured to enable air to substantially freely pass from the air space of the fork to the reservoir during a relatively low speed impact experienced by the fork, and to inhibit air from passing from the fork to the reservoir during a relatively high speed impact. This advantageously preserves desired shock absorbing characteristics for heavy shock absorption events, e.g., bumps at high speed, while still providing desired cushioned ride characteristics during low speed riding. This provides improved rider comfort and can help eliminate fork shaking, commonly referred to as head-shake, and other disadvantages associated with riding motorcycles having shock devices adjusted to withstand relatively hard impacts.
For example, an off-road racer or rider will typically adjust the fork to a setting corresponding to the hardest anticipated impact, such as a major jump, on the course or trail. This adjustment may be accomplished as by adding oil to the fork or adding a stiffer spring. Assuming a relatively hard impact is expected, this leaves the fork ill-suited for the remainder of the course as the fork is too stiff. The systems described herein advantageously provide a fork system that permits a rider to adjust the fork to a setting corresponding to the hardest anticipated impact, yet the fork is better suited for the remainder of the course that does not have such hard impacts. Thus, a rider utilizing a fork utilizing such a control system can experience improved comfort and control through the remaining portions of the course as compared to use of a fork not having such a control system.